Machinery for cutting screws



P. H. WATSON.

Screw Threading Machine.

Patented Dec. 3, I846.

'{UNITED STATES "PATENT OFFIC PETER H, YVATSON, OF ROCKFORD, ILLINOIS.

MACHINERY FOR CUTTING SCREWS.

Specification of Letters Patent No. 4,868, dated December 3, 184.6.

T0 all whom it may concern Be it known that I, PETER H. WVATsoN, of thetown of Rockford, in the county of WVinnebago and State of Illinois,have invented a new and useful Improvement in Machines for CuttingScrews, which is described as follows, reference being had to theannexed drawings of the same, making part of this specification.

Figure 1 isa perspective view of the machine as arranged for cutting amale screw upon a rod of metal. Fig. 2 is a view of the face of thebeveled cog wheel carrying the dies, cutter and rest, &c. Fig. 3 is avertical transverse section of the carriage and jaws for holding thematerial to be operated on. Fig. 4 is plan of the cutter. Fig. 5 is aplan of the tap in the act of cutting the thread in a nut.

The nature of this invention and improvement consists in combining andarranging in a suitable frame certain known mechanical principles insuch a way as to form a new and useful machine which will enable themechanic to make screws and nuts with greater despatch and correctnessthan by the modes now in use.

The combination consists of a cog wheel A and pinion B working into thesame supported by suitable frame work C, on a permanent bed D-said cogwheel having attached to its face two sliding dies E E of the usual formfor indenting the screw on the rod of iron F said dies being turned withsaid cog wheel which is caused to revolve by turning a crank G on theaxle of the pinion B while the rod of iron F is held in a horizontalposition between two vertical parallel jaws H attached to a slidingcarriage I moved in parallel grooves S in the bed toward the dies by thedraft of the dies and chaser on the rod in cutting the thread whichpasses through the hub of the wheel, made hollow for that purpose, thescrew being perfected and finished before passing through the opening inthe center of the wheel by means of an adjustable cutter or chaser J ofa shape corresponding to that of the thread to be cut, attached to theface of the wheel, between the dies and the wheel and directly behindthe dies and in a position to bring the cutter or chaser in contact withthe thread as marked by the dies so as to cut and perfect it as itleaves the diessaid cutter being attached to the face of the wheel by aset screw J passing through an oblong mortise in its shank. A forkedrest K isconnected to the cog wheel in the same manner as the cutter soas to bear against the screw 011 the side opposite to that where thecutter is placed being designed to 'support the screw while under theoperation of the chaser or cutter.

The dies are contained in and supported by a sliding frame L and aremoved by a right and left screw M attached by a collar to a stud Ninserted into the face of the wheel turned by a milled head, or othermeans without changing its position longitudinally, the right threadworking in a female head in the middle of the top of said sliding frameL and the left thread in a female thread in the middle of the slidingfollower which slides in the sliding frame the lower die being placedagainst the bot tom of the sliding frame, and the upper die against theunder side of the follower P so that when said screw is turned itcausesthe dies to approach or recede from, each other simultaneously, bygiving the follower and bottom of the frame similar movements inopposite directions.

The inner sides of the frame are made of a V shape to entercorrespondingly shaped grooves in the ends of the die plates andfollower. The outsides of the sliding frame are similarly shaped toslide in corresponding grooves made on the under sides of parallel ribsQ fastened to the face of the wheel. This arrangement is adopted for thepurpose of adapting the dies to various diameters of rods upon whichscrews are to be made, and for centering the dies and rod. The jaws forholding the rod of iron on which the screw is to be cut consists of twovertical parallel plates H H notched or recessed on their inner sideswhere they grip or clamp the rod F having their lower ends turned atright angles to enter and slide back and forth in parallel grooves R Ron the upper side of the sliding carriage I at right angles to thegrooves S in the bed in which the carriage I moves. These jaws areopened or closed by means of a right and left horizontal screw T turnedin corresponding right and left female screws in the jaws H H, saidscrew being prevented fro-m changing its position longitudinally byattaching-it to the head of a post U inserted into the carriage I by asuitable neck V formed in the middle of the screw between the right andleft threads, said neck turning tapered end of the tap into the hole inthe center of the piece of iron to form the nut and turning the crankaXle G the thread will be cut by the said tap.

The frame C containing the cog wheel and pinion may be made torevolvehorizontally on a pivot or center and the cog wheel may be madethe driver and the pinion the carrier of the cutting tools anddiesespecially in cutting screws of small diameter where speed isrequired.

What I claim as my invention and desire to secure by Letters Patent isThe combination of the right and left screw and sliding frame, with thedies for the purpose of centering, feeding, marking and smoothing thebolt while the screw is being out upon it by the chaserthe whole beingarranged and operated in the manner herein set forth.

P. H. WATSON. Witnesses:

WM. P. ELLIOT, J. FRANCIS MAHER.

